A common flushing apparatus for toilets involves a reseating flush valve that holds a large volume of supply water in a tank from which it is suddenly released into the toilet bowl. And a float valve is responsive to the water level in the tank to replace the water level, operating automatically and separately from the flush valve that is manually operated by movement of a flush handle or lever that is turned to lift the flush valve. A detrimental feature of this common system is that the flush valve tends to and eventually leaks, resulting in water waste.
Another flushing apparatus, common in the United Kingdom, involves a syphon tube having its suction leg depending into the supply tank so as to be filled with water, and its discharge leg normally empty of water and opening into the toilet bowl, and operated by means of a primer pump that is manually actuated to fill the discharge leg thereby initiating syphoning. The said primer pump operates as a water lifting means in the suction leg of the syphon. The advantage of this syphon system is that there can be no leakage from the supply tank through the inactive syphon. However, the pump means gradually deteriorates and requires repeated cycles of operation in order to complete a flushing of the toilet, and inevitably becomes inoperative.
In view of the foregoing, it is an object of this invention to employ the aforesaid syphon tube flush principle of operation to the exclusion of a pump means, and replacing the aforesaid pump-type primer means with a tank-type primer means, all in combination with an otherwise conventional toilet having a water supply tank but to the exclusion of the conventional flush valve.
The syphon principle of operation is superior with respect to the conservation of water, in that there can be no continuous leakage therethrough when its discharge leg is empty of water. And, only when the discharge leg is primed does water flow therethrough and through the flush tube. On the contrary, the flush valve principle of operation is prone to continuous leakage from the water supply tank and through the flush tube, due to deterioration of either the valve seat or valve ball element. It becomes apparent therefore that the syphon principle is superior, except for the inevitable deterioration of the pump means therefor which is typically a flap or disc of flexible material that lifts the tank water into the syphon and initiates continued flow therethrough until the water supply tank is emptied through the flush tube. Accordingly, these two widely used principles of operation are each subject to deficiencies, one to inherent leakage and the other to eventual inoperation. In view of the foregoing, it is an object of this invention to provide a toilet flushing apparatus that virtually eliminates leakage of the flush water control means, and that eliminates valve and/or pump devices as flush control means.
It is to be understood that the water supply tank is refilled after each flushing operation, by means of a conventional and accepted water level responsive valve means from a water supply service pipe. In practice, a float controlled valve returns the tank water level to the bridge of the syphon after each flushing operation.
The syphon principle of operation is characterized by two conditions, a passive condition wherein the discharage leg is dry, and a functioning condition wherein the discharge leg is wet. In order to achieve said wet condition priming is required for filling the otherwise dry discharge leg with water, whereby syphoning action is initiated and continues to occur. It is an object of this invention to prime the syphon by discharging a relatively small volume of water through the flush tube so as to have a jet pump effect on the syphon. In practice, the opening of the syphon discharge leg in to the flush tube forms a jet pump configuration that enables the syphon to function when flooded with a downward velocity of water suddenly dumped therethrough. Accordingly, the apparatus herein disclosed is characterized by a manually acutated primer means, preferably a dump tank, that floods the flush tube at a jet pump opening from the discharge leg of the syphon.